1. Field Of The Invention
This invention relates to transport trailers used in carrying fluids, and more particularly, to a figerglass transport trailer having no metal frame.
2. Description Of The Prior Art
Transport trailers with tanks of metal construction are well known in the art, but many problems arise when such trailers are used to carry corrosive fluids. One solution has been to coat the insides of the metal tanks with materials such as resins which are impervious to the fluids. A problem with such construction is that metal tanks are expensive, and the addition of the resin coating is additionally expensive. Further, if cracks or flaws appear in the resin coating, the corrosive fluid is again exposed to the metal tank.
Transport trailers with tanks made completely of fiberglass have been developed to address this problem. Most prior fiberglass transports still require a metal frame for adequate strength of the transport as it travels over the road. Such metal frames are expensive and add additional weight.
One chassis-less fiberglass tank truck is shown in U.S. Pat. No. 3,158,383 to Anderson et al. which discloses a fiberglass tank supported by forward and rear cradles. The tank includes internal ribs to which the cradles are bolted.
The present invention uses metal cradles which are molded to the exterior of the tank shell, and thus no bolting to the tank occurs. The only bolting is where the fifth wheel member and the rear wheel carriage are bolted to the cradles. Each cradle has a plurality of protrusions extending therefrom which are interwound by glass filament during the manufacturing process, thus resulting in a very rigid structure which can be used over a long period of time without maintenance.